Read more about cascade https://www.baeldung.com/jpa-cascade-types

There are 3 way to do it delete the category and set id null, second delete the category and product also third do not allowed to do delete category. to do this all in spring boot we used cascade= caseCadeType.—- It has multiple type which we can read in above link and add it in cordinality annotation like @OneToMany(fetch=, cascade=casecadeType.)